Sanofi and GSK announce a delay in their COVID-19 vaccine program

Dec. 15, 2020

Sanofi and GSK announced a delay in their adjuvanted recombinant protein-based COVID-19 vaccine program to improve immune response in older adults.

Phase 1/2 study interim results showed an immune response comparable to patients who recovered from COVID-19 in adults aged 18 to 49 years, but a low immune response in older adults likely due to an insufficient concentration of the antigen.

A recent challenge study in non-human primates performed with an improved antigen formulation demonstrated that the vaccine candidate could protect against lung pathology and lead to rapid viral clearance from the nasal passages and lungs, within two to four days. These results increase the companies confidence in the capacity of the adjuvanted recombinant platform to deliver a highly efficient vaccine for all adults.

Sanofi’s recombinant technology and GSK’s pandemic adjuvant are established vaccine platforms that have proven successful against influenza. The recombinant technology offers the advantages of stability at temperatures used for routine vaccines, the ability to generate high and sustained immune responses, and the potential to prevent virus transmission.

The Companies plan a Phase 2b study expected to start in February 2021 with support from the Biomedical Advanced Research and Development Authority (BARDA), part of the HHS Office of the Assistant Secretary for Preparedness and Response (ASPR) under contract W15QKN-16-9-1002. The study will include a proposed comparison with an authorized COVID-19 vaccine. If data are positive, a global Phase 3 study could start in Q2 2021. Positive results from this study would lead to regulatory submissions in the second half of 2021, delaying the vaccine’s potential availability from mid-2021 to Q4 2021.

Sanofi and GSK adjuvanted recombinant-protein based vaccine candidate was selected in July 2020 by U.S. government’s Operation Warp Speed in order to accelerate its development and manufacturing. The companies have updated governments and the European Commission where a contractual commitment to purchase the vaccine has been made.

A recent preclinical study using a highly virulent challenge in non-human primates, showed high ability for the vaccine to protect against lung pathology and reduce virus in the nose and lungs within two to four days. Results from this pre-clinical study confirm strong ability of the vaccine candidate to stop the replication of the virus with an optimal antigen formulation.

GSK has the release.

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